Filter device



FIG. 1 is a perspective view.

FIG. 2 is a left-hand side view.

FIG. 3 is a top view.

FIG. 4 is a bottom view.

FIG. 5 is a right-hand side view.

FIG. 6 is a front view; and,

FIG. 7 is a back view. 

The ornamental design for a filter device, as shown. 